A computer network is a geographically distributed collection of interconnected communication links and subnetworks for transporting data between nodes, such as computers. Many types of computer networks are available, with the types ranging from local area networks (LANs) to wide area networks (WANs). A LAN is an example of a subnetwork that provides relatively short distance communication among the interconnected stations, whereas a wide area network enables long distance communication over a larger geographic area using links provided by public or private telecommunications facilities. The nodes typically communicate by exchanging discrete frames or packets of data according to predefined protocols. In this context, a protocol consists of a set of rules defining how the nodes interact with each other.
Computer networks may be further interconnected by an intermediate node, called a router, to extend the effective “size” of each network. Since management of a large system of interconnected computer networks can prove burdensome, smaller groups of computer networks may be maintained as routing domains or autonomous systems. The networks within an autonomous system are typically coupled together by conventional intradomain routers. These routers manage communication among local networks within their domains and communicate with each other using an intradomain routing (or an interior gateway) protocol. Furthermore, the routers typical reroute information around network outages since typical inter-domain networks provide multiple paths between two end points. For example, Bidirectional Forwarding Detection (BFD) described in Request for Comments (5880), by D. Katz et al. (2010), provides a mechanism for a router to detect a communication failure with an adjacent router.
It is possible to measure the communication performance between two end points of a computer network. Active measurement protocols are a mechanism for measuring this performance. An example of such a protocol is the Two-Way Active Measurement Protocol (TWAMP) described in RFC 5357, by K. Hedayat et al. (2008). TWAMP defines how to measure the delay, jitter, packet loss ratio, and connectivity. Another example of such a protocol is described in TWAMP Value-Added Octets, Internet Engineering Task Force (IETF) Draft, by S. Baillargeon (2011), for extending TWAMP to measure capacity.